Nowadays, artists such as JW Waterhouse can be found in books on pre-Raphaelite painters alongside Rossetti and Millais yet Waterhouse would be more correctly classified as a Romantic Classicist.
The pre-Raphaelite movement began in 1848, when painters Rossetti, Millais and Holman Hunt found themselves revolting agains the trivial contemporary art in fashion at the time, and resolved on a revival of the spiritual and poetic.
Thus, popular themes illustrated were myths, poems and legends...
The Lady of Shalott, La Belle Dame Sans Merci, The Bath of Psyche are just a few examples.

Art themes popular with other Victorian painters were the whimsical depictions of children, preferably with baby animals; the 'hidden drama' of love and love lost; hunting scenes, and the idyll of landscapes and family life.

Other influences on Victorian style were things Egyptian (prompted by Howard Carter's and Lord Carnavon's discovery of Tutankhamen's tomb), Medieval and Gothic.